Variant 2-165913618-G-A details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_024753.5(TTC21B):c.2167C>T(p.Arg723Trp) variant causes a missense change. The variant allele was found at a frequency of 0.0000155 in 1,612,780 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R723Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

TTC21B
NM_024753.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.45

Variant links:

Genes affected

TTC21B (HGNC:25660): (tetratricopeptide repeat domain 21B) This gene encodes a member of TTC21 family, containing several tetratricopeptide repeat (TPR) domains. This protein is localized to the cilium axoneme, and may play a role in retrograde intraflagellar transport in cilia. Mutations in this gene are associated with various ciliopathies, nephronophthisis 12, and asphyxiating thoracic dystrophy 4. [provided by RefSeq, Oct 2011]

TTC21B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTC21B	NM_024753.5 linkuse as main transcript	c.2167C>T	p.Arg723Trp	missense_variant	16/29	ENST00000243344.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTC21B	ENST00000243344.8 linkuse as main transcript	c.2167C>T	p.Arg723Trp	missense_variant	16/29	1	NM_024753.5	P1	Q7Z4L5-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152020

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000160

AC:

AN:

250710

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135618

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000353

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000164

AC:

AN:

1460760

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726770

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000253

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000180

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152020

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74240

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.0000546

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Jeune thoracic dystrophy;C0687120:Nephronophthisis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 29, 2016

In summary, this variant is a rare missense change with uncertain impact on protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is present in population databases (rs201500142, ExAC 0.002%) but has not been reported in the literature in individuals with a TTC21B-related disease. ClinVar contains an entry for this variant (Variation ID: 216766). This sequence change replaces arginine with tryptophan at codon 723 of the TTC21B protein (p.Arg723Trp). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and tryptophan. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.14

BayesDel_addAF

Benign

-0.11

BayesDel_noAF

Benign

-0.34

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.38

Eigen

Benign

-0.044

Eigen_PC

Benign

-0.050

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.88

M_CAP

Benign

0.047

MetaRNN

Uncertain

0.52

MetaSVM

Benign

-0.74

MutationAssessor

Benign

0.55

MutationTaster

Benign

0.84

PrimateAI

Benign

0.34

PROVEAN

Uncertain

-2.5

REVEL

Uncertain

0.34

Sift

Uncertain

0.0030

Sift4G

Uncertain

0.010

Polyphen

0.95

Vest4

0.34

MutPred

0.68

Loss of helix (P = 0.1299);

MVP

0.40

MPC

0.15

ClinPred

0.85

GERP RS

4.3

Varity_R

0.17

gMVP

0.42

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.34

Details are displayed if max score is > 0.2

DS_AL_spliceai

0.34

Position offset: 28

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over